At present, treatment with ionizing radiation is widely used not only in the therapy of malignant neoplasms, but benign tumors and a series of inflammatory and other diseases of nonneoplastic nature as well (Aspects of Clinical Dosimetry, Ed. R. V. Stavitskij, Moscow, “MNPI”, 2000 [1] (in Russian)).
Devices are known for radiation therapy which comprise X-ray source, oriented for the purpose of directing radiation created with it to the pathological locus area. In order to minimize irradiation of healthy tissues surrounding pathological locus, such devices may comprise several X-ray sources. The irradiation created with them is directed to the pathological locus area from different directions (Radiation Therapy of Malignant Tumors. Guide for Physicians. Ed. Prof. E. S.Kiseleva, Moscow, “Meditsina” Publishing House, 1996 [2] (in Russian)).
Device is also known for radiation therapy comprising several X-ray sources whose radiation, being aimed to the area of pathological locus from different directions, is focused with X-ray lenses (international application PCT/RU 00/00273, WO 01/29845A16 26 Apr. 2001 [3]). Due to the said focusing, radiation from each of the lenses on passing through the healthy tissues has in them lower concentration than in the pathological locus.
More radical way to decrease irradiation of healthy tissues surrounding the pathological locus comprise its irradiation not from outside, but from the inside.
Such a way is realized, in particular, by implantation of a capsule with radioactive material directly into the pathological locus [2]. This method has drawbacks of the necessity of surgical intervention and associated with it difficulty in the control of irradiation duration.
The most close to the device proposed is a known device disclosed in U.S. Pat. No. 5,153,900 [4] (Russian analogue patent No. 2,155,413) and in number of other patents belonging to Photoelectron Corporation. This known device comprise a probe device for introduction directly into the pathological locus or for approaching it. Probe device in said device is a part of X-ray tube. Its anode is situated at the distal end of probe device. Proximal end of probe device adjoins the outlet of means for electronic beam formation, which is directed along the longitudinal axis of the probe device towards anode.
Within the probe of this device vacuum should be maintained (as within any X-ray tube). This fact in combination with the necessity of high voltage supply to the anode situated at distal end of a thin lengthy probe and the necessity to control position of electronic beam make for design complexity of the device. At that, radiation energy is determined substantially by anode material. Impossibility of anode replacement in the evacuated probe results in necessity of having separate device for each radiation energy desired. The same is true for changing spatial radiation pattern by matching the radiotransparency ratio of different portions of the distal probe end. Operation of the device utilizing electronic beam is influenced with external magnetic fields, thus necessitating to make arrangements on corresponding shielding. Realization of the probe as a part of X-ray tube complicates substantially its sterilization. Overcoming of this drawback by providing the probe with removable sheath increases its diameter and is associated with a rise in traumatism on utilization of the device. Therefore, primary field of utilization of said device is treatment of tumors of hollow organs requiring no puncturing and situated in immediate communication with outer environment, such as urinary bladder, rectum, etc. Besides, said device, comprising probe as a constituent part of X-ray tube, is applicable for treatment with X-ray radiation only.